Alex Morgan was just five years old when she saved her mother Tracy’s life by becoming her bone marrow donor. ‘‘My whole family was tested and Alex was my closest donor," said Tracy. "At the time, people asked me how I could let my child go through that, but my only other option was to let her grow up without a mother."

Now 24, Alex and her mom will take part in the Leukemia Foundation’s World’s Greatest Shave to celebrate the 20th anniversary of that successful surgical procedure.

Alex hasn’t had her long, dark hair cut for three years now, and plans to donate her hair to be made into wigs for people undergoing cancer treatment.

Despite her good intentions, she says she’s also got some ‘‘selfish’’ reasons for getting her head shaved.

‘‘I’ve been through some changes in my life, and I wanted to shave my head to signal a new start,’’ she said. ‘‘Plus, I’ve always wanted to know what it feels like to go for a swim in the ocean with a bald head!’’